Not much heat

[Kabel69]

Correct me if I'm wrong but the blend door redirects the air through the vents or defrost right. If so mine has been broken for a couple of years now, but I still have heat. What I have had problems with in the past when there is no heat is the thermostat quits working properly. The temp gauge will still read in the normal range or maybe a hair below normal. This happens about every 2 years and once I replace the thermostat I have heat. I have tried after market and OEM thermostats but have had the best luck with OEM.

You are correct....it seems everything is working fine and my coolant temps range from 185-194 and never venture over 194. It drops back down so I'm assuming g the thermostat is opening. All my friends swear the heater core is partially clogged. I've attempted to flush it multiple times and even poured some clr in it and let it sit for a few hrs and flushed it out real good.

I'm not sure I want to take on the task of pulling the dash out to replace the heater core but I also don't have the cash to take it to a shop either. I get flow out of the core when I flush it but if its not reaching all the channels of the core then maybe its not distributing the heat like it should.

I was getting 130 degrees out of the vents last night while sitting in my driveway holding at 2k rpm but only 109 degrees at idle. Temps ranged from 105-112 while driving on the highway this morning. Guess ill look into what it will take to replace the heater core.

 

[BrianL2017]

Any updates Kabel69, I have a 2002 that seem to be doing the same thing.

 

[Kabel69]

Any updates Kabel69, I have a 2002 that seem to be doing the same thing.

Yeah I just forgot to post back. I ended up pulling the dash out and replacing the heater core. It took me about 8 hours start to finish following this guide. Luckily I was able to remove half of the hvac box and not have to pull the evap coil so no need to vacuum down the ac system.

How to: Dash removal and Heater core change

 

[rocco123]

So heater core did fix it? ?

 

[Kabel69]

So heater core did fix it? ?

In my case, yes.

 

[jk7294]

I used to have this issue on my 2002 V8 Explorer and figured it was the thermostat. I replaced it and began noticing that the coolant level was going low every month or so and I would just fill it up. The coolant loss got worse and worse until I figured out that it had blown the intake gasket, very common on these engines. After replacing the intake with a Dorman model it fixed the coolant loss issue. By the way the intake manifold was completely trashed and I still have it. I may post some pics of the original 198k intake to show what they look like after that kind of mileage.

 

[Kabel69]

I used to have this issue on my 2002 V8 Explorer and figured it was the thermostat. I replaced it and began noticing that the coolant level was going low every month or so and I would just fill it up. The coolant loss got worse and worse until I figured out that it had blown the intake gasket, very common on these engines. After replacing the intake with a Dorman model it fixed the coolant loss issue. By the way the intake manifold was completely trashed and I still have it. I may post some pics of the original 198k intake to show what they look like after that kind of mileage.

Interesting. I haven't noticed any coolant loss yet but that is something to keep an eye on. I did notice a small amount of coolant in the grooves on top of my thermostat housing when I was replacing my alternator but that was gone when I went to look again the next day after driving. I will have to start diagnosing my rear heater once it warms up enough for me to want to open up that can of worms. I've got 186k or so miles on this beast and I'm just wondering what will break next lol.